Commercial printer R.R. Donnelley & Sons, Chicago, this week reported net income gains of 14 percent to $51 million, or 36 cents per diluted share, for the second quarter and 19 percent to $96 million, or 66 cents per share, for the first six months of 1998 as compared to the same periods a year ago. These increases exclude a $146 million pretax gain from the sale of the company's remaining interest in Metromail Corp. Revenue gains of $7 million to $1.1 billion for the second quarter and $66 million to $2.3 billion for the first six months were driven by Donnelley's magazine, telecommunications and financial-services business units. Earnings rose 22 percent to $97 million for the quarter and 22 percent to $185 million for the first half. Net income, inclusive of the Metromail sale, was up 56 percent to $58.7 million, or 41 cents per share, for the quarter and up 54 percent to $103 million, or 71 cents per share, for the first half. Chairman and CEO William Davis attributed the gains as well as improvements in operating margin and return on invested capital to continuous cost reduction and productivity improvement.